In order to study the electrochemical corrosion performance of as-cast and sintered AlCoCrFeNi high-entropy alloys in simulated seawater medium,vacuum arc melting and spark plasma sintering processes were used to prepare AlCoCrFeNi high-entropy alloys.Their structure and microstructure were analyzed in the XRD and OM,respectively,and the electrochemical test was performed in the electrochemical workstation.The results show that the AlCoCrFeNi as-cast alloy has an equiaxed morphology and its phase shows a single BCC structure; the sintered alloy has a spherical morphology.At 900 ℃ sintering temperature,a small amount of B2 and FCC phase as well as BCC phase appear.The sintered and cast self-corrosion potentials are -0.535 4 V and -0.667 6 V,respectively,and their self-corrosion current density are 2.914 9×10-5 A·cm-2 and 2.150 4×10-5 A·cm-2.The passivation zone of the as-cast alloy is wider than that of the sintered alloy.Both alloys have only one capacitive arc,and the radius of the capacitive arc of the as-cast alloy is much larger than that of the sintered alloy,which indicates that the corrosion resistance of the as-cast alloy is better than the sintered alloy at the current sintering temperature.